Life Cycle Assessment of Hydrogen Production Techniques

Abstract

The world is confronted with a pressing global climate crisis, and hydrogen is gaining ever greater recognition as a carbon-neutral energy carrier with the potential to significantly contribute to the process of decarbonizing economies. Nevertheless, the environmental consequences of various hydrogen production methods are occasionally underestimated. This chapter offers an extensive review (articles published from 2015 to 2023) of both environmental repercussions and costs associated with a wide array of hydrogen production methods. There are numerous technologies for hydrogen production, including thermochemical, electrochemical, and biological pathways utilizing renewable and nonrenewable sources. Nevertheless, the selection of these processes for hydrogen production relies heavily on environmental sustainability as determined by life cycle assessment (LCA). Hydrogen production LCAs have been categorized into four main stages including (i) defining the goal and scope, (ii) conducting a life cycle inventory (LCI) analysis, (iii) life cycle impact assessment (LCIA), and (iv) interpreting life cycle results, which are described in detail in this chapter. Finally, a comparison of the life cycles of various hydrogen production pathways is performed based on life cycle indicators. The initial comparison of the LCA studies focuses on global warming potential (GWP), followed by an evaluation of other metrics such as freshwater eutrophication or terrestrial acidification in low-GWP technologies. The findings reveal that technologies with the lowest GWP presently come at a higher cost, ranging from approximately $4 to $9 per kilogram of hydrogen, as opposed to the prevailing fossil fuel-based hydrogen production technologies, which cost roughly $1 to $2 per kilogram of hydrogen. © 2025 selection and editorial matter, Mohammad Reza Rahimpour, Mohammad Amin Makarem and Parvin Kiani.